Flow sensors, e.g. MEMS flow sensors, sense the flow of air or other gas across their surface. A typical application for flow sensors is in parts, in particular the wings, of aircraft. The flow sensors are typically required to be fitted in the aircraft component such that the sensing surface of the flow sensor is flush with the surface of the aircraft component.
Quite separately, it is known to use a large number of fasteners (e.g. screw, bolts etc.) to fix component parts of aircraft and other structures to each other.
In unrelated technical fields, it is known for certain other types of sensors, that do not need to be fitted flush to a surface, to be embedded within a central region of a fastener-type item as a way of allowing the sensor to be attached to a structure. For example, U.S. Pat. No. 7,134,334 discloses a motion detector embedded in a fastener-type item for attaching to an automobile. Although in U.S. Pat. No. 7,134,334 the item is called a fastener, it does not appear that the item is intended to be used as a fastener, i.e. to fix two parts of the automobile together, rather the item is apparently intended to be used only to attach the motion detector to the automobile. Additionally, the item does not appear to be readily formed in the same dimensions or shape as conventional fasteners. Furthermore, the item is such that the motion detector is not capable of being fitted flush to a surface as is desirable for a flow sensor. US 2007/0040663 discloses another sensor item that similar comments to the above also appear to apply to.